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what are signs of a bad 1g maf


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conditions for the cut out and the missfire are all over the place. im running the stock plug just cut the 1g plug on maf to allow the stock plug to fit its been working find for years now just started acting crazy. car has brand new plugs wires and cap and rotor new coil too Edited by ultraflexxj
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if it runs like crap at idle, and you unplug the mas, and nothing changes, it's probably the mas.

If you unplug the mas at idle, does it change, or run the same? If it runs the same, try driving it and see if it acts any different. If there is no difference, you have a bad mas.
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anyone know any signs of a bad maf my car just all of a sudden started cutting out missfireing and sometimes work ok

conditions for the cut out and the missfire are all over the place. im running the stock plug just cut the 1g plug on maf to allow the stock plug to fit its been working find for years now just started acting crazy. car has brand new plugs wires and cap and rotor new coil too

Cut out and miss fire are two different things to me. Can you describe the symptoms and circumstance of both better?

 

You can try another one. They are cheep enough. Even if the setup is the same, a problem with boost control or timing control could increase the airflow or induce a rich miss fire.

Edited by StarquestRescue
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Not to thread jack but this seems to relate to what I got going on I tried that (unplugging the MAS) and it ran just as bad.I have stock mas that was originally in the car and gonna try it.Now that I got other problems resolved and it will atleast run its belching black smoke.as if both injectors are running.as if the mAS thinks im running full boost.I have voltage at both injectors idling.....1.25 on one and 12 something on the other,the primary is the one with the 12 volts and the secondary is the 1.25 volt.i have to put secondary clip on the primary injector to get it to even run and leave te other pigtail unhooked,.wierd.i soldered on new leads for both yday and was carefull to do one wire at a time so I didn't get them switched. Or could I have an ECU problem causing them both to fire at idle?
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so it was a bad maf got it running with the stock maf untill my maf trans and gm maf get here. stock maf wont let me run much boost with all my mods though such as my large over bore and 18g turbo
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Glad ya got it fixed kinda easy with just swapping stock MAF back in.gonna try that on mine this weekend.will find another 1gen MAF soon.glad I kept it.I unplugged the 1st gen and nothing changed at all so I dig out the stock unit and aircan.
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Bad news symptoms are back. any ideas starts up fine runs ok for the most part untill you start to boost then will start to pull then violently loose power then start bucking and some times sputtering
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Bucking is lack of fuel. Check the advance unit too.

 

can be one of many things that can cause bucking,,the flames and back fire says too much fuel or spark miss fire ,sad thing is rarely will ONE cure fix every ones problem , a loose IC hose or split hose can do it under boost , I've seen connections push apart under boost and cause engine shut down , air mass over run and too much fuel when this happens,,,, mechanical adv system stick and not advance or stick in the advanced state ,,

 

this is why you have to set up a list of most likely causes and go down it one item at a time until you have been thru them all,,and DO NOT STOP at the first problem found,, more then one thing is normaly wrong

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all the i/c hoses were replaced with hard pipes i checked all the couplers for cracks. ive blown charge pipes off before i know what that feels like im going to check the vacuum advance and the mechnical advance see if iether are sticking.
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Bucking is still lack of fuel , so pretty much gotta spend a day with it. Compression check, fuel pressure check, pull plugs and look at condition. Go on test drive. Do more checks. Checks codes. Check fuel pressure under boost. Check injectors for leaks by clamping off return line while pump is on shine light down in t/b..

What plugs are in there? I had a set of ngk's just quit firing once spend all day swapping in in injector resistors and resetting the tps and then a set of ngk 7031's I had laying around went in and car ran great.

You can make a fuel pressure guage tester setup for 18 bucks from the hardware store.

 

Do all this stuff and take pictures and do a write up you'll be someones hero

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I always start with ignition. A miss at low rpm points to ignition or engine problem. I once had a bucking cutout problem that had a cracked head at the root of it.

 

The stock mas will easy over run or reach fuel cut with a 18g. Lots of variables here that effect how quick the turbo goes from a little to a lot of air flow and how much it spikes above the target boost. The stock or 1g maf do not do well with explosive spooling turbos that can move a lot of air and boost spike. That is why the slow spooling c compressors were popular in the pre maft days.

 

I see no mention of a wide band gauge, and as mentioned fuel pressure needs to be monitored under boost.

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